While the Army Eastern Macedonia and the forces of the 3rd Military District, deployed on the Bulgarian frontier, were falling apart under the blows of the German 12th Army, the troops commanded by Gen. Henry Maitland Wilson were still organizing defences along the line Aliakmon valley - Vermion mountains - lake Vegoritis - Kajmakcalan. The news about the Yugoslav debacle on the Vardar caused that Gen. Wilson began to worry that the enemy troops could reach the rears of his left wing. Upon an agreement with General Aléxandros Papagos it was decided that the left wing of the Greco-British troops would be evacuated from the sector Vegoritis - Kajmakcalan to the area of the pass Kirli Derven near Klidi, where they would build new defences blocking the northern approaches from Bitola. While the troops were already on the move, the news came that the enemy took Bitola. It meant that the Yugoslav defence in that area was broken, and the German command got an opportunity to engage more forces in Greece.

In such a situation Gen. Papagos decided to pull his troops from Albania to a new defence line: mount Olympus - mount Orliakos - lake Butrint. But such a manoeuvre required at least 12 days to be fully completed. On 12 April in the evening the troops from the Army Western Macedonia started their withdrawal, whose successful outcome depended on the Britons' ability to hold their positions at Klidi. Meanwhile, during the conference of Generals Wilson, Archibald Wavell and Sir Thomas Blamey in Larissa it was decided that the British Expeditionary Corps would retreat farther southward. Gen. Wilson simply assumed that the retreat was a manoeuvre too difficult to the Greeks, its success was dubious and their morale was fading. So he had shortened the time to hold Klidi; still the deadline was not met since the Germans on 12 April crushed there the Australian 19th Infantry Brigade and pushed it farther to the south. Then the German 9th Armoured Division was introduced to the fights. On 13 April it struck against the rears of the British 1st Tank Brigade, which in result retreated too far southward and the Germans seized Army Western Macedonia's only retreat route.

Meanwhile on the same day Gen. Wilson already had decided to retreat farther to Thermopylae; the retreat started at night 15/16 April. But it was not until the morning 16 April that Wilson, during his meeting with Papagos in Lamia, informed his Greek partner about this decision as a fait accompli. The Greek commander was shocked. Such a development of the situation could mean only one thing - defeat. Since Papagos had no influence on Wilson's decisions, he authorized his orders, but simultaneously requested evacuation of the British Expeditionary Corps from Greece. In the second half of April there started hectic probing of a formula to split the Allies and cease the resistance of the Greek army (practically encircled in the Pindus Mountains). Also the possibilities to evacuate the British forces from the continent were deliberated.

The command of the German 12th Army in Greece had as a rule incomplete and obsolete data about the enemy, but pushed its troops forward being convinced about their absolute superiority over the British expeditionary forces. Meanwhile the British command within five days beginning 16 April organized withdrawal of its troops to Thermopylae, where they assumed defence on 20 April, while the German pursuit got jammed in traffic in the valleys of Thessaly. So the British could boast about the orderly retreat, but they actually buried the last chance to pull the Greek forces out of Albania. They were left in the mountains. Having in the rear the Italians, who went to a counter-offensive, they encountered in front few but motorized and armoured German units. The Greeks found themselves in a trap. Generals started pressurizing Athens for a political solution, Athens answered with orders to continue fights.

The crisis was also mounting in the Greek capital itself. Some members of the government agreed with the generals and demanded a cease-fire with Germany, but simultaneously demanded continuation of the war with Italy. Others demanded evacuation to Crete and continuation of the war from there. The British Expeditionary Corps was still on the continent, but it had received orders from the British prime-minister, Sir Winston Spencer Churchill, to conduct resistance only as long as it would be conducted by the Greeks.

On 18 May, after several conferences, which opted for cease-fire, King George II decided that the prime-minister did not control the situation any more. The prime-minister Aléxandros Koryzis argued, that he had been always driven by the sense of duty and honour, and then left the conference highly agitated. As the king realised what was Koryzis' state of mind, he sent his best friend, Ioánnis Diakos to see the prime-minister at home. Upon his arrival Diakos asked Koryzis, how he estimated the situation. Koryzis answered that the answer would be given in a couple of minutes, after which he went to the bathroom where he shot himself dead. The prime-minister's suicide had aggravated the chaos in the Greek leadership.

Meanwhile on the Albanian front the generals decided that they had exhausted all the legitimate means. They removed the loyal commander of the Army Epirus, Gen. Ioánnis Pitsikas, and appointed in his place Gen. Geórgios Tsolákoglou. The same day Tsolákoglou agreed upon cease-fire with the commander of the Leibstandarte "Adolf Hitler", Josef (Sepp) Dietrich. The cease-fire was concluded between the Greeks and the Germans; the latter had to create a buffer between the Greek and Italian troops on the Albanian front. But Field-Marshal Wilhelm List by the order of Berlin annulled the agreement and ordered to sign a new one providing for unconditional capitulation; however he acknowledged the cease-fire between the Greeks and Germans and separation of the Greeks and Italians as a legal fait accompli. According to that acknowledgement the Greeks allowed German troops to pass. That caused an extreme unrest in Rome. Benito Mussolini, personally complained to Adolf Hitler, and the German dictator for political reasons decided to satisfy ambitions of his Italian ally. He sent to Greece Gen. Alfred Jodl, who induced Tsolákoglou to send truce envoys also to the Italians. In name of Germany he signed the third act of surrender - this time in Salonika. This time Italy was represented as an equal to the III Reich, although the act of surrender did not introduce anything new in the agreements with the Germans.

The events in Epirus decided about the events in Athens. A new prime-minister was appointed - Emmanouil Tsouderos, a political enemy of Ioánnis Metaxas. He made the decision to evacuate the government and the Royal Family to the Crete and continue the war from there. He also issued the official note to the British, in which he agreed for evacuation of their expeditionary corps.

The British Expeditionary Corps since 20 April was holding positions along the line Thermopylae - Bralos. Its evacuation was considered difficult, and its effect was estimated pessimistically. Preliminary preparations began as early as on 13 April, but the realization depended on the transport capacities of the British Mediterranean fleet. The fleet meanwhile was engaged in secondary tasks off the Libyan coasts and was not able to operate in the Greek waters before 25 April. Towards the end of April both Greek and British air forces were eliminated as a considerable factor in the hostilities and the German Luftwaffe possessed the full command in the air. As the British skillfully masked their movements and positions, the efficiency of the German air forces on the continent was little, but in the sea they were sinking ships at will. It was not until 24 April that the Germans had finally got their traffic under control and started advance on Thermopylae. The advance debacled in the fast defence of the Australian and New Zealand troops that were left there to cover the British evacuation. The British started their withdrawal to the Greek ports already at the night to 24 April.

During the pursuit towards Athens the German command announced a victory at Thermopylae (which was not), but in fact it had no clue where the British troops were. The air reconnaissance reported that they had evacuated, the radio reconnaissance reported that they were still on the continent. As they did not know what was the real picture, the Germans staged an airborne landing at Corinth to impair a possible British retreat from Megara to the Peloponnese. But that had introduced only minor changes to the British schedule. Although on 27 April German troops entered Athens, several British groups literally got out of the trap, as they were evacuated from the ports of eastern Attica. The last British unit was evacuated from the Peloponnese at the night to 29 April. Altogether about 50,000 men were saved from the Greek drama, but they had to leave all their heavy weapons and equipment on the continent. Also substantial were losses in ships. Greece had found herself under the fascist occupation. Only one scrap of the Greek soil remained free - Crete.